reinforced Concrete retaining wall supporting an under-pinning operation
version or scroll down for photos
footings are dug and the back wall is lined first with Geo-Textile
material to allow just the water through to the waterproof steel
reinforced wall, and no silt. This passes down the inside of the
structure into the porous pipe "French Drain" located
at the base. Steel mesh cages are built on-site and by hand because
there is limited space and access for the heavy gage steel.
see that the structure will have a cantilever foot and anti-roll
peg at its base to ensure that the structure is unable to rotate
from the current incline. Once in place the micro piles will be
drilled through the end of the foot to further ensure no rotation.
plastic membrane is to ensure that none of the concrete passes into
the Geo-Textile material or into the crevices of the original stone
wall. This is to ensure that there remains a clear path for the
water to drain from the wall, through the Geo-tex into the French
drain at the base and then away. The extra plastic above and to
the sides is to protect the walls and patios of the house.
spacers are added to make sure that there is sufficient gap between
the steel and the wall for the concrete to pass behind. The shuttering
along the top is to stop any concrete splash over.
is then loose pumped into the foundation and vibrated to remove
From this angle you can see that
the concrete gets pumped right into the base of the foundation ensuring
that the whole wall and foot section are poured as one solid unit.
add pressure to the hose which forces the concrete into the cage
structure. This compacts to form a very strong concrete wall. The
quantity of cement in the mixture is very high producing a very
quantity and the presure make the concrete very sticky, perfect
for building up the layers around the steel.
build up until the steel mesh starts to disappear. This wall for
example is 50cm thick at the base tapering to 40cm at the top. A
very solid structure!
is then leveled off so that the depth is constant along the whole
area. In this case the surface is made rough finish as we are going
to add stone pieces to finish the wall. The rough surface together
with a special chemical will help bond the stone pieces to the concrete
we have begun cladding the retaining wall with heavy grade stone
pieces. Although the surface of the concrete was left rough we first
pain the wall with a bonding agent to ensure that the pieces stick
are built up, first fixed on and then pointed or grouted with a
retaining wall was a dry stone wall, typical of the Moraira / Costa
Blanca area. We matched the stone colour as closely as possible
so that when all is finished it will be difficult to notice that
the retaining wall was retrofitted.
proved to be very dificult to set right, but the outcome was fantastic.
you can see that even though the stone is rough cast the levels
of the wall have remained true.
As you can see, corner going in
well and the stone is creeping to the top.
the stone cladding is finished we reconnect new down pipes for the
cracks in the old block walls are opened and treated with a flexible
cement, and then repainted.
never know that we had built a 40 ton steel reinforced cantilever
wall, it all looks original.
painted and finished. Many thanks to the clients, David and Jeannine
in Moraira, a pleasure working with you!